<?php if (!defined('THINK_PATH')) exit();?><!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="utf-8">
    </head>
    <body>
        <form action='/thinkphp/firstproject/index.php/Home/Index//calc' method="POST">
            <input type="text" name="text" value="<?php echo ($sum); ?>">
            <input type="submit" name="submit" value="测试">
        </form>
    </body>
</html>